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groovyBC for gradual inlet velocity

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Old   March 31, 2011, 04:17
Default groovyBC for gradual inlet velocity
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Samuel ARNAUD
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Hi everyone,

I'm doing a 2D forced convection case with chtMultiRegionSimpleFoam (steady case). I had no problem with relatively slow inlet velocity, but for higher one (100m/s), it diverged at some time!!!

I have tried all I could find in the forum to solve this problem: modified relaxation factors, tolerances, MaxCo number, timesteps, etc... but none was effective (it only delayed the crash).

I bet I can do several cases with gradually higher velocities each (mapping the results of previous case into the next one, and so on). That would be time consuming (not a problem for a 2D case, indeed,but for further studies in 3D...), therefore, I'd like to know:

With this great tool (groovyBC), how would you define the inlet velocity such as varying from 0 m/s to 100 m/s? with a kind of "log"like shape?
My knowledges in this matter are really weak

If this subject has already been discuss in another thread, please, be kind to redirect me to it

Best regards
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Old   March 31, 2011, 09:09
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Samuel ARNAUD
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My bad guys,

I discovered timeVaryingUniformFixedValue and it seems to be perfect
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Old   April 1, 2011, 18:48
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Charlie
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How do you implement it? I'm very interested in this It does not render your model to blow up?
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Old   April 4, 2011, 02:58
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Samuel ARNAUD
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Hi Charlie,

Yes it does... I'm still working on it to solve the matter
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